Parsimony failure in Class Aves

Good thing people like you have the ability to sense the difference between homoplasy and synapomorphy a priori.

As for me, I'll trust to the consensus of most actual workers in this

There is hope. Cladists are making progress. They no longer claim that Mononykus is a bird. Give them time. Maybe one day they will realize that Protarchaeopteryx and Caudipteryx are actually birds, not theropods. Can't be too greedy, can we?

Note that that cladogram means to merely places them as _Paraves incertae sedis_. Thus, they could conceivably be avians. We really need a well-preserved basal alvarezsaur.

Looking over some literature, and considering the new basal troodontid (_Sinovenator_) just published, it looks like this might be a better consensus:

Maniraptora Alvarezsauridae Avimimidae

For those interested, a summary can be found at

They could not be avians or even avialans according to the consensus tree above, since Aves and Availae are both nested inside Eumaniraptora. and Mononykus is definitely outside of Eumaniraptora.

It amazes me that every time a new theropod is discovered, it becomes the definitive proof of a theropodan origin of birds and/or the missing link between birds and theropods. Caudipteryx and Protarchaeopteryx were supposed to be feathered oviraptorosaur theropods that were intermediate between theropods and birds. Rahonavis was once considered such a link. Then NGMC 91, a dromaeosaur, was supposedly the best evidence for a feathered theropod. And now a troodontid is supposedly the new missing link. There are so many missing links that birds must have evolved several different times from different groups of theropods according to the cladists. BTW, Brochu claimed in the past that Troodontids had birdlike teeth, but this claim was apparently originally made by Currie and Feduccia (1996) disputes this claim and points out that the illustrations of the teeth do not support this claim.

Keesey apparently does not realize that he has just demonstrated why strictly cladistic classifications are so unstable. They are unstable for two different reasons (Mayr and Ashlock 1991):

1. Slight changes in the topology of a cladogram can result in drastically different classifications.

2. Any two different cladist or two different cladistic analyses from the same cladist may disagree strongly on the relationship of the same group of organisms.

As for the claim that the new dinosaur had a bird-like shoulder joint, that is probably wishful thinking and most likely a product of creative reconstruction. It does not make any adaptive sense for a theropod to have an avian shoulder joint. The fact that it has a wishbone means nothing since Longisquama also has a wishbone. Plesiomorphs cannot be used to assert a close relationship, as Harshman points out. The claim that it has a pelvic bone that points backward is ironic, since Archaeopteryx was once reconstructed by some supporters of the dinosaurian origin of birds to have a theropodlike ventrally oriented pubis! IOW, some paleontologists seem to be fitting evidence to conform to the dinosaurian origin of birds. If theropods have ventrally oriented pubes, then Archaeopteryx must have had the same. And if evidence now shows that Archaeopteryx had retroverted pubes, then they better start reconstructing theropods with retroverted pubes as well. As Feduccia points out, some theropods do have partially retroverted pubes, but retroverted pubes are also found in ornithischian dinosaurs. It is a highly homoplastic character. So the new buzz over Sinovenator is based probably on an erroneously reconstructed shoulder joint, the plesiomorphic furcula and a highly homoplastic character like the retroverted pubes. And this sort of dubious evidence is supposed to prove that birds are descended from dinosaurs?

One way to conceal one's ignorance is to impersonate a physicist in a biology forum, as several aliases of the cyberstalking loon (namely Bob Keeter, 'Eric J. Korplea' and John Brock) had done. But their attempts at deception failed when all three of them failed to cite even a single passage from a textbook to substantiate their identical claims. As I said, the most favorable odds that I can give to the chance that three 'physicists' stumbling onto the same paleontological forum and that all three are unable to cite textbooks to support their identical claims is at best 1/100 x 1/100 x 1/100 or 1/1,000,000 (one in a million). The chance that they are the same cyberstalking loon is almost certainly 100%.

Another way to conceal one's ignorance is to say as little as possible. It is this second strategy that Osama bin Cyberstalking Loony has adopted in this particular post.

Perhaps the notation I was using was unclear. In a diagram like this:

A B

And just what does this have to do with me? All I did was supply a link.

I'd rather wait to read the paper before commenting, unlike some people...

Feduccia does not claim anything of the kind. He says that *therizinosaurs* are almost certainly not related to coelurosaurs, and that there are simply too many differences amongst the various families of dinosaurs and birds to say for sure which descended from what. One dismisses what Feduccia says at one's peril. His words are not the rantings of an idealogue. They are the carefully thought-out observations of a very deep thinker in the field. He raises some very cogent and convincing points about avian evolution and cladistics in general. I would not be too hasty in poo-pooing him.

john thrum

Therizinosaurs are coelurosaurs, and whether Feduccia wants to accept it or not is another matter. However, I do think they are more primitive coelurosaurs than are the oviraptorosaurs (Order Caenagnathiformes), and so I am getting flack from the cladists for not including therizinosaurs in my Class Aves. And they seem stunned that I place Archaeopteryx in a more primitive position than Caenagnathiformes, Caudipteryx, and Protarcheopteryx. Caudipteryx is clearly a bird that is close to pygostylians. Anyway, I am an equal opportunity critic, and will criticize eclecticists if they are wrong just as readily as I will criticize strict cladists. I certainly do agree with Feduccia that purely cladistic classifications (which forbid formal paraphyletic groups) are a dumb idea, and also that cladistic analysis is often done poorly (due to an over-reliance on strict parsimony). But as an Ashlockian systematist, I will not throw the baby out with the bathwater, and will use cladistic analysis as a tool. Moderation in all things. Even Feduccia himself admitted to me that cladistic analysis could be a useful tool, and I can certainly understand his frustration with the sloppy way in which is it often practiced. But he shouldn't let that blind him to the mounting evidence that oviraptors and mononykiforms are birds (or near to birds, depending on where you draw the line).

Sounds like another dogma.

Convince him! He questions this hypothesis because therizinosaur teeth are not like those of coelurosaurs. Instead, their teeth bear a striking resemblance to those of prosauropods. Their upright stance and retroverted pubis is probably an adaptation to having a large stomach for fermentation, according to David Norman's analysis of retroverted pubis in bipedal vegetarian dinosaurs. Their vegetarian diet supports that interpretation. Their vegetarian diet also contradicts the claim that they are coelurosaurs.

The pygostyle appears to have evolved independently in the enantiornithine and orithurine birds, according to Hou et al. (1996, Sci.). If Kinman is latching onto another convergent similarity, then it is nothing new.

Please. There are no 'eclecticists.' Please call them by their proper name: Darwinians or traditionalists or evolutionary systematists. There is no shortage of names for your opponents, but you insist on using a pejorative but uninformative one.

But you are yourself a strict cladist. I don't see any criticism of strict cladists from you. In fact, you defend them habitually. You even defend cladograms that show birds descending from dinosaurs and artiodactyls being sister taxa to whales.

Kinman also disrespects Feduccia, calling him part of the 'fringe.' Kinman is being disingenuous if he claims that he is objective.

That is not accurate. Ashlock does not destroy paraphyletic taxa. Kinman does.

Actually Kinman doesn't want to throw out the bathwater. Both cladistic analysis and cladistic classification are bath water. There is no baby in this tub.

Yes, use it. But use it sparingly, as the botanist A. Cronquist advises us. Don't rely on it as though it will lead us to objective truth, as Kinman thinks it will.

Yes, Feduccia even used it himself in Hou et al. (1996). As I said, if one has a set of good characters, it does not matter what methods one uses. Even phenetics can give a reasonably accurate estimate of relationships if one has a set of good characters. The fact is that cladists use superficial similarities, just like the pheneticists. There is no method that could provide a sound phylogenetic hypothesis when all one has are bad characters.

His frustration stems from his opponent's attempt to fit the 'square peg' of evidence into the 'round hole' of the dinosaurian origin of birds theory (Feduccia 1999:405). He writes (1999:386), for example:

'Without reiterating the arguments of chapter 3, we can clearly see that no line of evidence will convince these paleontologists that Archaeopteryx and Confuciusornis were arboreal birds.'

What can be more frustrating to a scientist (or any scholar for that matter) than an opponent who either ignores evidence or who fits evidence into theory? And it appears that Kinman is just as impossible to convince as any strict cladist or dogmatic subscriber to the dinosaurian origin of birds. It appears that he also fits evidence into theory.

I find it ironic that Kinman is calling anyone blind. It is he who is blind. He openly ignores the 'mountain of evidence' that Feduccia (1996, 1999) has proffered to refute the dinosaurian origin of birds. Kinman has ignored the close relationship between Longisquama and birds. He is simply hopelessly enamored with cladism, and will subvert scientific truth to help the cause of cladism. Kinman is not a scientist, but a quasi-religious fanatic who is hopeless enamored with cladism. In other words, Kinman will sacrifice scientific truth at the altar of cladism, just as any hardline cladist will do without hesitation.